gistfile1.txt

my int $j = 2;
my int $cnt = 0;
my int $mult = 2;

CNT:
loop (;;)
{
    $mult +<= 1;
#    my $x = Str($mult);
    my $x = ~$mult;
    if $x.chars() == 16 {
        $mult div= 10;
    }
    if $x.starts-with("123") {
        last CNT if ++$cnt >= 678910;
#        say("Found $cnt => $j") if $cnt +& 1023 == 0;	# this is slow
    }
    ++$j;
}
say("Found $cnt => $j");